<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        /* display:flex  //默认是row显示 */
        .parent{
            width:1000px;
            height: 300px;
            background: red;
            display: flex;
            /* flex-direction:row/column */
            /* flex-direction: column; */
            /* justify-content:设置横坐标方向的对齐方式  space-around |space-between */
            justify-content: space-evenly;
            /* align-items:设置纵坐标方向的对齐方式 */
            align-items: center;
        }
        .parent div{
            width:150px;
            height: 200px;
            border:2px solid #333;
        }
    </style>
</head>
<body>
    <div class="parent">
        <div></div>
        <div></div>
        <div></div>
        <div></div>
    </div>
</body>
</html